Liquid fill control

ABSTRACT

A liquid fill control for an automatic washing machine which shuts off the inflow of water into a washing machine when a preselected water level has been reached. An impervious bellows is mounted within an accumulator in the washing machine, and communicates by means of a pneumatic tube with a pressure switch which controls a water inlet valve. The pressure switch is preset by an operator to correspond to a desired water level for the wash load, and influent water into the washing machine deflects the bellows in an amount proportional to the hydrostatic head thereby increasing the pressure upon the pre-set pressure switch through the pneumatic tube until the pressure switch operates to close the water inlet valve.

United States Patent Worst 5] June 20, 1972 (541 LIQUID FILL CONTROL 3,367,153 2/1968 Brubaker et al. ..68/207 x [72] Inventor: Joeeph C. Worst, Louisville, Ky. Primary Examiner wmiam L Price [73] Assignee: General Electric Complny Attomey-Walter E. Rule, Francis H. Boos, .lr., Frank L. Neu- [22] Filed: Nov. 16 1970 hauser, Oscar B. Waddell and Joseph B. Forman [2 I] Appl. No.: 89,830 [57] ABSTRACT A liquid fill control for an automatic washing machine which [52] US. Cl 68/207, 68/214, l37/387, shuts off the inflow of water into a washing machine when a 200/33 WM preselected water level has been reached. An impervious bel- 1 III.- Cl. lows is mounted wihin an accumulator in the [58] Field of Search ..68/12 R, 12 F, 207, 23.4; machine, and communicates by means f a pneumatic 137/387, 403, 453; 200/83 WM, 83 A, 83 C with a pressure switch which controls a water inlet valve. The pressure switch is pre-set by an operator to correspond to a Rem-mas Cmd desired water level for the wash load, and influent water into UNITED STATES PATENTS the washing machine deflects the bellows in an amount proporttonal to the hydrostatic head thereby Increasing the pres- 2,592,314 4/1952 Morton ..68/207 X sure upon the pre-set pressure switch through the pneumatic 2,885,879 5/1959 Bloom ..68/207 tube the pressure switch operates to close the ink! 3,102,409 9/1963 Paganini ..68/207 X va|ve 3.l87,l 37 6/1965 Morey..... ...68/207 UX 3.362.197 1/1968 Reed ..68/207 X 3 Clalrrs, 1 Drawing Figure PATENTEDJHM'eU m2 INVENTOR, JOSEPH c. WORST ms ATTORNEV BACKGROUND OF THE INVENTION A washing machine may be used by the operator to launder a wide variety of wash loads. In a top loading, agitator type washing machine, it is desirable and most efficient to proportion the water level in the washing machine to the wash load. If a light load is to be washed, then only a low level of water is needed; if a heavy load is to be washed, then a full level of water is required. If the level of the water is not proportional to the wash load, then, a washing machine becomes inefficient in terms of water and detergent consumption.

One way to proportion the water level to the wash load level is to have the operator stand by the washing machine and shut ofi the water when a sufiicient water level is reached. This is time consuming on the part of the operator and inconsistent with the operation of an automatic washing machine.

Another way to control the level of fill is to place a timer on an inlet valve of a washing machine, and pre-set the timer to shut down the inlet valve afier a certain period of time. This method is disadvantageous because a change in the water pressure of the influent water could result in an error in the level of fill.

Various other automatic liquid fill controls have been found in the prior art which automatically regulate the liquid fill level. One such system, in a top loading, agitator type auto matic washing machine is shown in US. Pat. No. 2,885,879, Bloom. It provides a tubular air trap connected at one end to a variable control pressure switch which electrically controls a water inlet valve, while the other end of the tubular air trap is in communication with the wash tub. As the inflow water rises in the wash tub it physically displaces air in the air trap, causing a rise in pressure until the pressure switch is closed and the inflow of water is shut off. There are two primary disadvantages to this system. Wash water, flowing into the air trap to physically displace air, tends to leave a residue of detergent and lint which clogs the air trap after the wash water has been drained. The other disadvantage in this prior art, is that, the system requires a variable control pressure switch which is more costly than a standard non-adjustable pressure switch; and, because the switch must be placed in the control panel it requires a more extensive wiring harness.

SUMMARY OF THE. INVENTION In accordance with the present invention, a top loading, agitator type, automatic washing machine is provided with an automatic liquid till control which shuts off an inflow of water into a washing machine when a preselected level of wash water has been reached. Influent water enters a washing machine through an electrically operated solenoid inlet valve and then is proportionately divided between a wash basket and a wash tub having a relatively small volume accumulator connected to the bottom thereof. An impervious, flexible bellows is sealed against an opening in the floor of the accumulator forming an air trap within the accumulator. One end of a pneumatic tube is connected to the bellows through the opening in the floor of the accumulator while the other end of the pneumatic tube is connected to a pre-set pressure switch which is electrically connected to the solenoid inlet valve. The pressure switch electrically controls the flow of influent water through the solenoid inlet valve by shutting off current which keeps the valve open. As wash water enters the accumulator, the weight of the volume of wash water, or the hydrostatic head, presses against the bellows in the accumulator causing air in the air trap to be forced out of the air trap and into the pneumatic tube which results in an increase in pressure upon the pre-set pressure switch. When the pre-set pressure upon the pressure switch is reached, the switch will operate, causing the solenoid inlet valve to shut off, thereby stopping the flow of water.

In one embodiment of this invention, a variable control pressure switch is used. If a variable control pressure switch is used, it is of the type in which a pre-set pressure setting of the pressure switch is mechanically controlled by a means within the switch itself.

OBJECTS OF THE INVENTION It is an object of this invention to provide an automatic liquid fill control system for a top-loading, agitator type automatic washing machine which will automatically shut oh the flow of water into the washing machine when a pre-selected water fill level has been reached.

It is an object of this invention to provide an automatic liquid fill control system which will be sealed against contact with wash water to avoid contamination by the wash water.

Other objects and advantages will be apparent from the following description of the invention and the novel features will be particularly pointed out hereinafter in the claims.

BRIEF DESCRIPTION OF THE DRAWINGS The invention is illustrated in the accompanying drawing in which:

FIG. 1 is a partially cutaway, elevational view of a top-loading, agitator type, automatic washing with the present invention applied thereto utilin'ng a variable control pressure switch.

DETAILED DESCRIPTION OF THE INVENTION Referring to the drawings, there is illustrated a top-loading, agitator type automatic washing machine including a wash basket 12 in an outer cabinet forming a tube 10. Access to the wash basket is provided through an opening 16 in the top portion of the outer cabinet and a hinged cover 18 attached to the cabinet. A suitable control panel 20 is also provided on the washer cabinet.

The lower portion of the washer cabinet also houses a driving unit 22 which is driven by a motor 23 energized by an external alternating current source (not shown). This mechanism, through means including a drive shaft 24, operates a bladed agitator 26 during the washing cycle of the washing machine. The motor and the drive shah also spin the wash basket during the drying cycle and activate a drain pump 28 during the drying cycle of the washing machine. This pump is adapted to discharge water only during die drying cycle.

Water, at the proper temperature, flows into the washing machine through a pair of inlet pipes, one of which is a hot water pipe 30, the other pipe being a cold water pipe 32. The water then passes through an electrically energized solenoid self-closing inlet valve 34 and into a mixing chamber 36. The mixing chamber has two outlet openings which proportionately divide water flow between the wash basket and the wash tub. A larger diameter outlet opening 38 directs water into the wash basket while a smaller diameter outlet opening 40 directs water into the wash tub and hence into an accumulator 42 connected to the bottom of the tub. The accumulator has a capacity of, for example, about one gallon and the outlets 38 and 40 are so proportioned that the basket and accumulator are filled with water in about the same time interval.

During filling, all of the water which is introduced into the wash tub flows into the accumulator. The accumulator is shown in the accompanying illustration as being connected to the bottom portion of the wash tub by a pipe 46. In the lowest portion of the accumulator, there is a drain outlet 50 which passes water to the drain pump 28 and then out of the drain pump and the washing machine through drain pipe 56 during operation of the pump.

According to the present invention, there is also provided an airtight, impervious, flexible bellows 60 on the bottom of the accumulator where it is subject to the hydrostatic head pressure of water in the accumulator. The bellows is connected by pneumatic tube 64 to a variable control pressure switch 68 which is located in the control panel. The pressure switch is electrically connected to the inlet valve so that upon a predetermined increase in pressure on the pressure switch, the solenoid will be de-energized and closed, the level of water in the accumulator which causes this action depending, of course, on the setting of the pressure switch.

During the wash and rinse cycles, the accumulator remains filled with water so that the hydrostatic pressure on the bellows keeps the water valve closed. During a spin or drying cycle, the one-way pump reverses and draws water from the machine and accumulator through drain 50 and discharges this water through drain 56. When the accumulator is empty, the pressure switch is reset, it being understood of course, that at this point the timer control for controlling the automatic operation of the washer has opened additional switch means in series with the pressure switch preventing operation of the water valve until the controls are set for another wash or rinse phase.

it will be understood that various changes in the details, material, arrangements of parts and operating conditions which have been herein described and illustrated in order to explain the nature of the invention may be made by those skilled in the art within the principles and scope of the invention.

Having thus set forth the nature of the invention. what is claimed as new is:

l. In an automatic washing machine, including a wash tub having an accumulator, a wash basket mounted within the wash tub, an electrically driven motor operatively connected to the wash basket and to a bladed agitator mounted in the wash basket, a drain pipe from the accumulator, and an intluent water supply; a liquid flll control comprising:

a. an electrically operated water inlet valve;

b. means in communication with the water inlet valve, which proportionately divides the influent water supply between the wash basket, and the wash tub and the accumulator;

c. an impervious bellows mounted within the accumulator;

d. a pressure switch electrically connected to the water inlet valve and pneumatically connected to said bellows; whereby, water flowing into the accumulator will increase the pressure on the pressure switch through the bellows and operate the pressure switch to cause the water inlet valve to close.

2. An automatic washing machine according to claim 1 in which said accumulator includes a drain in the bottom portion thereof.

3. An automatic washing machine according to claim 2 including a pump connected to said drain operable to empty said accumulator only during a spin or dry cycle.

i i i l i 

1. In an automatic washing machine, including a wash tub having an accumulator, a wash basket mounted within the wash tub, an electrically driven motor operatively connected to the wash basket and to a bladed agitator mounted in the wash basket, a drain pipe from the accumulator, and an influent water supply; a liquid fill control comprising: a. an electrically operated water inlet valve; b. means in communication with the water inlet valve, which proportionately divides the influent water supply between the wash basket, and the wash tub and the accumulator; c. an impervious bellows mounted within the accumulator; d. a pressure switch electrically connected to the water inlet valve and pneumatically connected to said bellows; whereby, water flowing into the accumulator will increase the pressure on the pressure switch through the bellows and operate the pressure switch to cause the water inlet valve to close.
 2. An automatic washing machine according to claim 1 in which said accumulator includes a drain in the bottom portion thereof.
 3. An automatic washing machine according to claim 2 including a pump connected to said drain operable to empty said accumulator only during a spin or dry cycle. 